#include <string_view>
#include <string>
class Base
{
public:
	virtual ~Base() = default;
	Base(std::string_view str) : m_str{str} {}

private:
	std::string m_str;
};

class Derived : public Base
{
public:
	using Base::Base;
	Derived(int i) : Base{""}, m_int{i} {}

private:
	int m_int{0};
};

int main()
{
	Derived s1{2};
	Derived s2{"Hello World"};
}
